56 



MACROMOLECULAR COMPLEXES 



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A BCD 



Fig. 1. (A), (B), (C), (D) Diagrammatic derivation of the coiled-coil structure 

 of the collagen macromolecule. Each of the three polypeptide chains is wound 

 about its own axis as a left-handed helix in a threefold screw fashion. The 

 axes are located at the vertices of an equilateral triangle and are parallel. The 



the collagen fibrils; see Glimcher, 1959, Glimcher et al., 1960a, and 

 Figs. 3, 4, 5), the possibility that either the macromolecular struc- 

 ture or the macromolecular aggregation state of collagen is respon- 

 sible for the induction of calcification by acting as a catalytic hetero- 

 geneity (similar to Agl in the case of supersaturated water vapor) 



